Fix for next highest power of 2 function.

sbates130272 · Mar 11, 2015 · 21ff9c8 · 21ff9c8
1 parent 3c31e91
commit 21ff9c8
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Showing 2 changed files with 18 additions and 3 deletions.
diff --git a/src/readthrd.c b/src/readthrd.c
@@ -180,10 +180,17 @@ static ssize_t check_file(const char *f)
     return ret;
 }
 
-
 static int next_power_of_2(int x)
 {
-    return (x & -x) + x;
+    x--;
+    x |= x >> 1;
+    x |= x >> 2;
+    x |= x >> 4;
+    x |= x >> 8;
+    x |= x >> 16;
+    x++;
+
+   return x;
 }
 
 struct readthrd *readthrd_start(const char *fpath,

diff --git a/src/writethrd.c b/src/writethrd.c
@@ -200,7 +200,15 @@ static int check_file(const char *f, int truncate)
 
 static int next_power_of_2(int x)
 {
-    return (x & -x) + x;
+    x--;
+    x |= x >> 1;
+    x |= x >> 2;
+    x |= x >> 4;
+    x |= x >> 8;
+    x |= x >> 16;
+    x++;
+
+   return x;
 }
 
 struct writethrd *writethrd_start(const char *fpath, const char *swap_phrase,